Theses and Dissertations at Montana State University (MSU)
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Item Impact of cattle feeding-style on beef and human postprandial inflammation(Montana State University - Bozeman, College of Education, Health & Human Development, 2024) Spears, Meghan Leigh; Chairperson, Graduate Committee: Mary P. Miles; This is a manuscript style paper that includes co-authored chapters.Purpose: Various cattle-feeding styles have arisen in recent years, impacting the sustainability and environmental practices of many producers. While these changes are known to have an impact on the environment, little is known about the direct impact cattle raised using different feeding styles has on human health. Acute response focused studies, like this, are a glimpse into the expected impact of a certain food on the diet over time. The purpose of this study is to investigate the impact of cattle-feeding style on postprandial inflammation. Methods: A randomized, double blind, crossover study design was used to compare grass-fed (GRA) and conventional (CON) beef. Subjects (n=10) were comprised of men and women with a healthy body mass index (BMI) and no preexisting metabolic conditions. Blood samples were collected fasted and postprandially for four hours. Blood samples were analyzed for inflammation markers (TNF-alpha, IL-23, IL-17, IL-10, IL-1beta, IL-6, IFN-gamma and GM-CSF) at hourly timepoints. To observe postprandial changes with and without consideration for cattle feeding style, the net area under the curve (AUC) was calculated. Maxchange and CMAXtime were calculated by finding the maximum value of each cytokine between hours one and hour postprandially and subtracting that from the fasting value. CMAXtime represents the time at which the maximum value of each cytokine was reached in hours. Maxchange and AUC responses were compared to zero using a one-sample t-test to determine if response was greater than fasting. Results: In response to beef, maxchange of all measured markers and IFNgamma AUC were significantly greater than zero (p< 0.05). No differences were shown between GRA and CON in inflammation AUC (p> 0.05). Conclusion: This demonstrates that beef consumption does increase postprandial inflammation, but cattle-feeding style does not significantly impact this response.Item The influence of dam age and heifer post-weaning voluntary feed intake on subsequent production, reproduction and lifetime productivity of Angus beef females(Montana State University - Bozeman, College of Agriculture, 2022) Wellnitz, Krista Rose; Chairperson, Graduate Committee: Megan Van Emon and Timothy DelCurto (co-chair); This is a manuscript style paper that includes co-authored chapters.Limited research has been done to evaluate the impacts of dam age or post-weaning voluntary feed intake and its impact on subsequent performance and longevity in the beef herds, specifically female offspring. Therefore, the objectives of this research were to investigate how dam age and post-weaning voluntary feed intake influences lifetime productivity of commercial Angus females. First-calf heifers and mature cows were used to conduct three studies. Results indicate that classification of replacement heifers based on intake as a heifer had little to no impact on subsequent productivity as a mature female, while dam age had a greater influence overall. Productivity as a measure of total pounds of calf weaned through 5 yrs indicated that cows from dams that were 8-yr old or older weaned more total pounds of calf than cows from 3- yr old dams. Results indicated that heifers classified as low intake heifers, had greater mature BW at breeding and greater BCS than cows that were classified as average or high intake as heifers. However, DMI expressed as g/kg of BW displayed no differences with respect to cow age. Milk production was influenced by post-weaning intake for 2 and 5-yr old cows. The dam age study, indicated that dam age will affect future outcomes of replacement heifers. Cow BW at weaning displayed significance for dam age with cows born from 5- and 8-yr old and older dams having greater BW than cows born from 2-yr old. Cow yearling weight was significant for dam age with cows from 5-, 6/7-, and 8-years and older dams having greater yearling weights than cows from 2- and 3-yr old dams. The probability of remaining in the herd at 5-yr old varied across dam age groups with cows from 2-yr old and 5-yr old dams having greater probability to remain in the herd than the other age groups. Therefore, our research suggests that selection of replacement heifers based on post-weaning voluntary feed intake at 45 d post-weaning is not a strong indicator of lifetime productivity. Instead, cow age has a greater impact on lifetime productivity than heifer post-weaning voluntary feed intake.Item Corn versus barley in beef cattle finishing diets: effect on steer performance, feeding behavior, and ruminal environment(Montana State University - Bozeman, College of Agriculture, 2021) DelCurto-Wyffels, Hannah Margaret; Chairperson, Graduate Committee: Megan Van Emon; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Corn versus barley in finishing diets: effect on steer performance and feeding behavior' in the journal 'Animals' which is contained within this dissertation.; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'The influence of environmental conditions on intake behavior and activity by feedlot steers fed corn or barley-based diets' in the journal 'Animals' which is contained within this dissertation.; Hannah M. DelCurto-Wyffels, Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Diurnal ruminal pH and temperature patterns of steers fed corn or barley-based finishing diets' in the journal 'Animals' which is contained within this dissertation.While corn is the most common feed ingredient in the United States, barley, which is more suitable for the growing and climatic conditions at northern latitudes, can be a common feed alternative to corn. The different digestive utilization of unique feedstuffs coupled with extreme environmental conditions can pose challenges to efficiently feeding cattle in different climates. Thus, to further our understanding of the use of barley in feedlot diets at northern latitudes this study evaluated the effects of barley and corn finishing rations on feedlot performance, feeding behavior, and ruminal environment. For two consecutive years, Angus-based yearling steer calves were fed in a feedlot trial (427.3 + or - 3.7 kg; n = 48 in year 1, and 406.8 + or - 3.4 kg; n = 47 in year 2). Steers were randomly assigned to one of two primary basal grain dietary treatments: 1) Number 2 feed corn or 2) Hockett barley. Steers were fed in a GrowSafe system to measure individual animal intake and behavior throughout the duration of the study. Twelve steers per treatment group for each year of the study were also fitted with a HOBO pendent G accelerometer to measure activity and a SmaXtec ruminal bolus for continuous rumen monitoring of temperature and pH. Limited differences were observed in regard to performance and eating behavior of steers fed corn or barley-based diets. The steer's diet interacted with short term environmental changes to influence animal feeding behavior, but diet had limited impact on cattle lying activity. Continuous ruminal monitoring revealed average daily ruminal pH and temperature were not impacted by diet; however, diet did affect daily variation in ruminal pH and temperature. Intake patterns were also different between corn and barley-fed steers in which corn-fed steers consumed more feed the first 6 hours directly after feeding while barley-fed steers consumed more feed later in the day. Presumably, these intake patterns could be influenced by differences in diurnal patterns of ruminal pH between corn and barley. Depending on cost and production year, both barley and corn can be high quality feedstuffs to use in beef cattle finishing rations.Item The influence of heifer post-weaning residual feed intake on subsequent production, reproduction, grazing behavior, supplement intake behavior, dry matter intake and milk production of Black Angus beef cattle(Montana State University - Bozeman, College of Agriculture, 2021) Parsons, Cory Todd; Chairperson, Graduate Committee: Timothy DelCurto; Julia Dafoe, Samuel Wyffels, Tim DelCurto, Darrin Boss and Megan Van Emon were co-authors of the article, 'Impacts of heifer post-weaning residual feed intake classification on reproductive and performance measurements of first, second and third parity Angus beef' in the journal 'Translational animal science' which is contained within this dissertation.; Julia Dafoe was a co-author of the article, 'The influence of residual feed intake and cow age on body weight and body condition change, supplement intake, resource use, and grazing behavior of beef cattle winter grazing mixed-grass rangelands' in the journal 'Animals' which is contained within this dissertation.; Julia Dafoe, Samuel Wyffels, Tim DelCurto and Darrin Boss were co-authors of the article, 'The influence of residual feed intake and cow age on dry matter intake post-weaning and peak lactation of Black Angus cows' in the journal 'Animals' which is contained within this dissertation.Residual feed intake (RFI) is a recognized measure of biological efficiency in beef cattle. However, RFI determination is expensive, time consuming and not well studied in beef cattle fed forage-based diets, nor how post-weaning RFI influences grazing behavior, supplement intake behavior or dry matter intake at different ages and physiological stages of production. Thus, the objectives of this research were to investigate how post-weaning RFI influences reproductive and productive performance, grazing behavior, supplement intake behavior as well as dry matter intake at different ages and physiological stages of production. A commercial herd of black Angus cows were utilized to conduct three experimental studies. Results indicate that classification of RFI for replacement heifers had little to no effect on subsequent beef cattle production and reproductive efficiency through the weaning of the 3rd calf. Subtle differences were denoted for cow Julian birth dates based on RFI classification and conception of 1st calf-heifers categorized as low RFI. However, heifer post-weaning RFI had little effect on subsequent cow performance (BW or BCS), grazing behavior, supplement intake behavior, and resource use. In addition, cow age significantly influenced cow performance, grazing behavior, supplement intake behavior, and resource use. We also observed high individual variability in grazing site selection, suggesting that individual-level factors may be driving grazing resource use and grazing behavior. Heifer post-weaning RFI did not influence mature cow dry matter intake, and this was consistent for both lactating and non-lactating beef cows. In contrast, cow age did correspond to quadratic increases of DMI and intake rates of mature cows. However, when DMI was expressed as g x kg body weight-1 no differences were observed with respect to cow age in lactating and non-lactating cows. Milk production was influenced by heifer post-weaning RFI for 2/3 and 5/6-yr old cows. Therefore, our studies suggests that selection for low RFI females would not impact overall herd productivity of cattle on foraged-based production systems, and that cow age has more of an impact on resource use, supplement intake, and grazing behavior, as well as DMI than heifer post-weaning RFI while grazing dormant-season mixed-grass prairie rangelands.Item Utilizing sugar beets in steer backgrounding, sheep nutrient metabolism, and silage(Montana State University - Bozeman, College of Agriculture, 2017) McGregor, Ian Robert; Chairperson, Graduate Committee: Megan Van Emon; C. M. Page, W. C. Stewart and M. L Van Emon were co-authors of the article, 'Effects of sugar beets on steer backgrounding performance, sheep nutrient metabolism, and ruminal characteristics' submitted to the journal 'Journal of animal science' which is contained within this thesis.; J. G. P. Bowman, C. M. Page, A. R. Hubbard, M. Manoukian, W. C. Stewart, and M. L Van Emon were co-authors of the article, 'The effect of ensiling sugar beets on preservation characteristics, nutrient profile, and in situ disappearance' submitted to the journal 'Journal of animal science' which is contained within this thesis.Non-harvested sugar beets are an abundant yet underutilized feedstuff for producers in Montana and Northern Plains region. A performance and metabolism study were performed to observe the effects of sugar beets on steer backgrounding performance, sheep nutrient metabolism, and rumen fermentation characteristics. Both experiments utilized four dietary treatments where sugar beets replaced 0% (0SB), 15% (15SB), 30% (30SB), and 45% (45SB) of barley on a dry matter (DM) basis. Forty eight Angus steers were used in a completely randomized design to conduct the 50 d performance study. Average daily gain (ADG), feed efficiency (G:F), and dry matter intake (DMI) weren't affected by treatment (P > or = 0.06). A 4 x 4 replicated Latin Square design was used to observe the effects of increasing dietary inclusion of sugar beets on nutrient metabolism and rumen fermentation characteristics of eight growing wethers. Crude fiber, DM, and nitrogen (N) digestibility weren't affected by treatment (P > or = 0.10), while N balance demonstrated a cubic effect (P = 0.04). Butyrate concentration demonstrated a treatment x time effect (P = 0.01), where butyrate concentrations increased with increasing sugar beets in the diet at 1300. The acetate to propionate ratio demonstrated a linear increase (P = 0.03) with increasing sugar beets in the diet. Overall, we concluded that sugar beets can be included up to 45% of the diet without inducing any deleterious effects on steer performance or sheep nutrient metabolism. However, the moisture content of sugar beets creates difficulty when storing this feedstuff, and we hypothesized that sugar beets may ensile well with other feedstuffs. Therefore, we carried out a study to test this hypothesis using a 3 x 2 factorial design. Treatments were hay (H), or sugar beets mixed with either hay (SBH) or soybean meal (SB) were ensiled at a rate of 50:50 (as fed) with or without a mold inhibitor. The pH of all treatments fell below 5.0 before d 90 (P < 0.01). All treatments increased in crude fiber and crude protein over time (P < or = 0.03). With these results, we conclude that sugar beets can be effectively ensiled with hay or soybean meal.Item The nutritive value of mixed prairie : sagebrush-bunchgrass and forest-alpine ranges for grazing cattle(Montana State University - Bozeman, 1978) Strazdas, Petras; Chairperson, Graduate Committee: J. E. (John Edgar) TaylorItem The effects of self-feeding various levels of safflower hulls in pellet form for maintaining yearling ewes(Montana State University - Bozeman, 1964) Brownson, RogerItem The effects of sheep grazing for Pisum sativum or Melilotus officinalis cover crop termination(Montana State University - Bozeman, College of Agriculture, 2016) Westbrook, Jasmine Katherine; Chairperson, Graduate Committee: Craig CarrIntegration of sheep grazing into crop rotation systems has been proposed as an alternative to conventional cover crop management techniques. However, the effectiveness of this approach and its impact on subsequent crops has not been evaluated in Montana. This study assessed the use of sheep (Ovis aries) grazing to terminate field pea (Pisum sativum) and yellow sweetclover (Melilotus officinalis) cover crops used in rotation with winter wheat. Cover crops were terminated using either rotational or continuous grazing treatments and their effects on cover crop termination, sheep live weight gains, and winter wheat emergence and yield were quantified. Sheep grazing for cover crop termination was also compared to chemical termination and mechanical tillage. In 2013, yearlings grazed the winter pea cover crop for 32 days. Sheep grazing was an effective termination method (77% dead, 1% live, 22% bare ground). Average daily gains (ADGs) did not differ between grazing treatments with sheep exhibiting ADGs of 0.181 kg day -1 for rotational (230 sheep ha -1)and 0.154 kg day -1 for continuous (57 sheep ha -1) treatments (P = 0.12). Winter wheat seedling emergence post grazing was higher under the continuous grazing treatment (P = 0.017), however winter wheat yield did not differ between treatments (P = 0.91). Results indicated grazing was a viable method for terminating a pea cover crop. In 2014, yearlings grazed the sweetclover cover crop for 40 days. Sheep grazing at stocking densities of 44 and 178 sheep ha -1 did not provide effective termination (40% dead, 34% live, 9% bare groundcover). Average daily gains did not differ between grazing treatments with sheep exhibiting ADGs of 0.177 kg day -1 for rotational and 0.172 kg day -1 for continuous treatments (p = 0.79). Termination was achieved using a second group of sheep at stocking densities of 119 and 477 sheep ha -1. Winter wheat seedling emergence did not differ between grazing treatments (p = 0.95). Winter wheat yield was lower in grazed plots than tilled and chemically terminated plots. Grazing has the potential for effective cover crop termination comparable to tillage or herbicide, but results may vary with cover crop species.Item The in vitro digestibility and utilization of Big Sagebrush and Black Sagebrush(Montana State University - Bozeman, College of Agriculture, 1985) Striby, Karl DavidItem Nutritional evaluation of 2-rowed barleys selected for high-lysine(Montana State University - Bozeman, College of Agriculture, 1976) Stutz, Duane Kip